Allergy Research Group QuatreActiv Folate the glucosamine salt of 5-methyltetrahydrofolate (5-MTHF). This new patented form of 5-MTHF has demonstrated greater bioavailability than the 5-MTHF calcium salt form. It also shows enhanced solubility and stability. Recommended use: Take 1 capsule one or two times daily, or as directed by a healthcare professional.